I've been chatting with skype for a long time.. and I don't know why, but for X time it's fine, and then it's too quiet..

Here how it goes :

I'm booting the PC -> getting into a skype call with friends -> talking with friends on skype -> (everything goes well) -> Closing the skype call -> Going back to a skype call like a hour after -. They can't hear me well, I have to shout so they'll hear me, and in the settings, it's on 100% + 30 DECIBELS, so I can't raise it higher...

and if I'll re-boot my PC, it'll be well until I'll close the skype call again..

Every time I'm skyping with friends well, and then when I close the call and come back after a while, they hear me really low(volume)..

I've been trying to fix this problem for about 2 months! If you'll be able to help me, I'd be so happy.

(btw It's connected not through USB, but through a microphone connection and headphone connection...) Also, I got Windows 7..